Move ember-source/types imports

Author: gitKrystan

addon-test-support/adapter.ts

@@ -1,7 +1,3 @@
-// FIXME: Remove
-import 'ember-source/types';
-import 'ember-source/types/preview';
-
 import { assert } from '@ember/debug';
 import hasEmberVersion from '@ember/test-helpers/has-ember-version';
 import Ember from 'ember';

types/dummy/index.d.ts

@@ -0,0 +1,2 @@
+import 'ember-source/types';
+import 'ember-source/types/preview';